The present invention relates to the diagnostic imaging arts. It finds particular application in non-axial pediatric diagnosis using computed-tomography (CT) and will be described with particular reference thereto. However, it is to be appreciated that it is also applicable to non-pediatric applications and imaging scenarios, and is not limited to the aforementioned applications.
In a slice mode, CT scanners procure image data by taking a plurality of contiguous slices of a subject and reconstructing them into a volumetric representation. Typically this is done by taking axial or near axial slices, that is, taking slices that are substantially perpendicular to a longitudinal (head to toe) axis of a subject.
In a spiral mode, volume images are collected by moving the x-ray beam through a spiral trajectory around the longitudinal axis. Commonly, the source rotates continuously while the patient support moves longitudinally back and forth.
A limitation of present devices is that patients are inserted head-first or feet-first. Often, only a few slices along a major axis of an organ or tissue of interest are necessary. Organs and anatomical structures that have large longitudinal profiles such as the spine or lungs require many axial slices to generate a single longitudinal slice.
The generation of numerous axial slices is time consuming, plus penetrating radiation can be harmful to living cells. Not only is the tissue in the longitudinal slice of interest irradiated, all tissue in the axial planes around the longitudinal slice of interest are irradiated from many directions. In particular, cells that divide rapidly are more susceptible to radiation than slower dividing cells. In general, children are more susceptible to radiation damage than adults simply because they are growing and their cells are dividing faster. When using penetrating radiation to image children, it is desired to keep the dosage as low as possible and limit the irradiation, as much as possible, to the specific slices to be displayed. In addition, children tend to be more restless than adults. Thus, motion artifacts become problematic, especially in temporally longer scans. A more efficient method of imaging portions of the body with large axial profiles which lessens exposure and scan time is desirable.
Another problem with imaging children is that an attendant frequently remains close at hand to assist in keeping the child still, as well as to comfort the child. Although the attendant does not enter the imaging region, she still receives a nominal amount of scattered radiation. Over many scans of many different children, the received dosages of the attendant becomes problematic.
The present invention provides a new and improved method and apparatus that overcomes the above referenced problems and others.
In accordance with one aspect of the present invention, a computed tomography apparatus is given. Radiation from a source is detected by an array of detectors and reconstructed into an image representation of a patient within the apparatus. A patient support that provides support for the patient in a seated position within the apparatus is located on a patient couch.
In accordance with another aspect of the present invention, a method of diagnostic imageing is given. A subject is positioned in a seated position within an imaging region of a CT scanner. A source emits radiation into the region and is detected after it traverses the region. The detected radiation is converted into corresponding electronic data and reconstructed into an image representation.
In accordance with another aspect of the present invention, a patient seat for use in conjunction with a third or fourth generation CT scanner is given. A back support that supports an upper torso of a patient in an upright position rests upon a base portion that supports the weight of a patient. The base portion and back support fit inside a bore of the CT scanner.
One of the advantages of the present invention resides in shorter scan times.
Another advantage resides in less received dose by the patient.
Another advantage resides in improved image quality.
Yet another advantage resides in the ability to procure non-axial image slices.
Still further benefits and advantages of the present invention will become apparent to those skilled in the art upon a reading and understanding of the preferred embodiments.